Manufacture of sheets or plates of manganese steel.



-others' skilled the art to which it apper- OF 'N'EW YORK, N. Y.

rraxoracruanlor snnn'rs oarraras or momma srnnn v Specification ofLetters Patent.

Application filed January 10, 1812. Serial No. 310,878.

To all whom it may eoncem: I Be itlknown that I, Wmrmno S. Porran, acitiz'enof the United States, and residing at the Ap, org Apartments,:atthe corner of 6. Broadwa. an Seventy-eighth street, .in the boronhwof Manhattan, in, the city, county,

and; tate=of New York, have inventedcer- .t'ain new, and usefulImprovements in the Manufacture of Sheets or Plates of Manand I dohereby declare the j ollowing to be a full, clear, and exact de--scriptionof the invention, suchras'wvillenabg tainsttomake and usethesame a In an ap lication for Letters Patent of the United tateqfiledby me under date of November'4th, 1911, Serial No. 658,425, Ihave-described the manufacture of sheets or 3 plates frommanganesesteelbil-lets or blanks 1 (having g8 percentage of manganeseabove 5; percent. and usually containing about 12 7 gr the finalvproduct of the operation ing of a substantiall uniform, fine edcondition throng out, and :having the desired stifinessor ductilityappropriate to the usewfor which it ,is intended; V

In my application referred to, the method described involves firstheating the manese steel :billet or sheet bar until it is Er d ught intoa uniform and ductile condition throughout, ,appro riate to the rollingo tion'. Tothislen ,the necessary plasticity is imparted to the billetor sheet bar, by raising it to a temperature whiehrfor the 85 notion ofthe best results, will usually above the melting .point of the eutecticalloy, that is, above 1 125 G. (ea-y H25 .C.

to 1225" 0., according to the ductility required-for =rolling), butwhich, in some in- 40 stances, may he-asllow :as 1060 (3., provided.

submuent' reduction from the billet to the sheetror plate in .a singleheat is not consid- 1 In accordance .with the present invention,

the blank in the condition of ductility to which it :has been :brooperation referred to, will :be thoroughly worked, by a partial rollingoperation, which terminates .at .a temperature from to 800 {0. to 10W.0., andithereafter continu- I ing the rolling. ration with lightpressure and slight uctions (according to the stifiness -.des1red) until.at the completion of the 0 ration, the-,stemperature has fallen'so lowtreversion ,outof the .uniforrmaustenite condition of thexmetal isimpossible.

htaby the heating In; the ractice the present invention,';the 1n1t1aleating of the blankis preferably Patented Feb. 20,1912.

carried to temperaturesabove 1125" 0., {and the rolling, "u to the timeof nearly completm there uction tofinished dimensions, shoul be-carriedon rapidly, with considerable reductions in each stage of the rollin sothat the steel is brought to a fine-grain wrought condition. Thereafter,the rol a wing; 1s preferably conducted inrolls whic are supplied with aconsiderable amount of cooling water, is so conducted that in each p agethrough these rolls, the metal is not nsidera' 'ly reduced or elongated,thereby stiffening of the roduct. This seco roll tinue unti :the metalapproaches a black heat, or even below the black heat, that is,-

at temperatures ranging from 550 C. to 400? C., or lower.

It is characteristic of the present invention that :rolling in theordinary manner, that isnyto say, with hea reductions, is avoided attemperatures be ow 800 0., and particularly below 720 0., below whichlatter -,temper ature rolling with hea reductions leaves the metal im avery st' :and brittle condition, similar to that produced by thecold-rolling or wire-drawing of mild steel, so that in such case, :asubsequent annealing operation is necessar to relieve the sheet orplateof strains or StlfillGSS. I have found, however, that by continuingthe rolling at temperatures below this limit with ,a moderate amount ofpressure, such, for example, as the weight of the ordinary sheet ,rollbut with inconsiderable reductions or elongations, the metal is not onlytough because of the avoidance of the excessive reduction at the lowerheat, but ma be cooled entirely without having so cred those separationswhich would 'have wcurred during the cooling if not accompanied by thepressure of the rolls. For exam le, if the plate were brought tofinished imensions by rolling until at a tem stature of above 720 andthen air-coo ed until at the ordinary temperature, the air-cooled sheethavin sufiered alterations in cooling from 720 to 420 would lack thedesired'ductility andtouglmess; whereas, subjected to the pressure ofthe rolls with but light reductions, the separations which might have attemperatures below 720 C. are avoided, and the finished sheet voidingany undue strainmfi or a n my an coinci entcool-ingshouldbeconis strongand tough, and has-a ductility correspondmg to the temperature at whichthe heavy reductions were terminated and the lighter reductions begun.

'By' sing wateron the rolls during therolling with but light:reductions, the more rapid cooling incident to the contactlwith thecold,wetvrolls further tends to obviate the separations incident to: slowcooling without applied pressure.

vHaving thus descrlbedf, intention, -what Iclaimlis;

l. 1.. The methodof making sheets or plates of. manganesesteel, whichcomprises heating a billet or blank of manganese steel,until in 1auniform and. ductile condition thr'ough out, partially. rolling until:in, a thoroughly worked condition at temperatures. which, m

f the; finishing stage of, the partial rolling,

are between 800? C, and 10? 5 6., thereafter working with light pressureand but slight ured uctions until the temperature-has fallen solow that;reversion out of the uniform,

; austenite condition will not take place; substantially .fiS described.

2. "lhe method of making sheets or plates of manganese steel, whichcomprises heatmg a uniform and ductilecondition throughout, I

a billet or blank of manganese steel until in partially; rolling, untilin a thoroughly worked condition at temperatures which, in

the finishing stage ofthe-partial rolling, are between 800 C. and 107 50., and thereafter working with'light pressure and but-slightreductions, together with gradual water- Vquenching until thetemperature has fallen so low xhat reversion out of the uniform,austenite condition will not stantially as described.

3. The method 'of making sheets or plates of manganese steel, whichcomprisesheat:

ing a billet o'r'blank of manganese steel 1111-- til in a uniform; and"ductile condition throughout, partially rolli'ng until in a thoroughlyworked condition at tem eratures which, 'in the finishing stage oi thepartial rolling, are between 800 G.- and 107 5 C.,and thereafterworkingzwith light pressure and but slight reductions-to,substanbtiailly 'a black heat {substantially as descrre "In testimonywhereof I affixinj signature; .in presence i take place sub-'

